Technologies for vehicle-to-vehicle communication and vehicle-to-infrastructure communication (C2X communication) on the basis of cellular mobile radio are known. Floating car data are likewise already known.
C2X communication is typically associated with WLAN-based communication technology. The most important application for the C2X communication is for warning about vehicles in a concealed approach, e.g. at junctions. In this context, a junction assistance function is also referred to.
For the C2X applications, a frequency band at 5.9 GHz is cleared (to be more precise: between 5875 MHz and 5905 MHz). Unfortunately, radio waves in this frequency range are absorbed by houses, shrubs, parking cars, etc., in exactly the same way as visible light. For this reason, direct communication between the vehicles at a junction does not become possible until the vehicles are in visual contact with one another, as a result of which the benefit of C2X communication for the junction assistance function is limited. In the license-free ISM bands (Industrial, Scientific, and Medical Band, frequency bands below 1 GHz), visual contact must not be absolutely necessary, in contrast to the 5.9 GHz frequency band, but the available band width in that case is significantly lower.